1. Field of the Invention
The present invention relates to a photoelectric conversion apparatus and an imaging system for use in a scanner, a video camera, a digital still camera and the like.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. 2003-259227 discloses a technique of reading signals from a column memory by two horizontal scanning circuits that operate in different phases, multiplexing the outputs from two horizontal output lines, and outputting the multiplexed outputs, in a CMOS image sensor. By doing so, a signal can be output from the CMOS image sensor at a frequency higher than the drive frequency of the horizontal output lines, and a photoelectric conversion apparatus with a high frame rate can be realized.
However, the CMOS image sensor as in Japanese Patent Application Laid-Open No. 2003-259227 has the following problem. In order to read a signal to the two horizontal output lines from the column memory in different phases as described above, the first column selecting line that provides electrical continuity between the column memory and the first horizontal output line in one phase, and the second column selecting line that sequentially provides electrical continuity between the column memory and the second horizontal output line in the other phase are included. There arises a problem that the first column selecting line capacitively couples with the second horizontal output line, or the second column selecting line capacitively couples with the first horizontal output line resulting in a superimpose of noise in the signal reading time period.